Timo Tjahjanto (Indonesian: [tʃahˈjanto]; born Timothy Tjahjanto; 4 September 1980) is an Indonesian film director, producer, and screenwriter known for his film works mainly on the horror and action genres. Tjahjanto owns the film production company Merah Production.

Apart from directing, producing, and writing stories for his own films, Tjahjanto is also known as one half of The Mo Brothers with friend and fellow filmmaker Kimo Stamboel. The duo received a Citra Award nomination for Best Director in 2016 for Headshot, while Tjahjanto himself won the Maya Award for Best Director in 2019 for May the Devil Take You.